Basin flyover and second tunnel proposed

Two major moves to streamline Wellington traffic flows have taken a step forward.

The New Zealand Transport Agency has applied for resource consent to build a flyover next to the city's Basin Reserve which it hopes to have finished by 2017. It also confirmed plans to build a second tunnel through Mt Victoria by 2022.

The flyover and adjacent work will cost $90 million and the second tunnel $300 million.

The work is part of the Levin to Wellington airport link, which has been declared a Road of National Significance. The agency says there is congestion in many parts of this route.

The proposed flyover would be shielded from sports fans by a three-storey, 65-metre-long building on the northern edge of the ground.

A second tunnel is envisaged, and the road on the airport side of the tunnel would be increased from two lanes to four, down from seven under a previous scheme.

The scheme is supported by the Wellington City Council, the Wellington Regional Council and the Basin Reserve Trust.

Wellington Regional Council chairperson Fran Wilde said on Tuesday that the work is absolutely essential.

"The Basin Reserve is the biggest traffic jam in the region and one of the biggest ones in the country. To get this done will make a huge difference to business in Wellington, to commuters and then of course obviously airport and hospital access. So this will definitely help."

The NZTA said there would be more open space, tree planting and cycleways.